little barley

First described in 1818 by Thomas Nuttall, Hordeum pusillum, also known as little barley, is an annual flowering plant native to the majority of North America, mainly the United States and southwestern Canada. It is a member of the subfamily Pooideae in the grass family Poaceae. The plant itself is approximately 14–40 cm (5.5–15.7 in) tall and is self-fertilizing. Leaves and spikelets are alternate. The flat, pubescent leaves can range anywhere from 2.4–12.7 cm (0.94–5.00 in) in length and 2.0–4.5 mm (0.079–0.177 in) wide. The sheath of little barley can be either glabrous or pubescent and wraps loosely around the stem. The inflorescence ranges between 4–8 cm (1.6–3.1 in) long. Of the three alternating floral spikelets, only one is fertile. The plant's growth period is during the winter months, producing mature grains by April. The roots are fibrous, and the mark of a mature spikelet is when they turn a tan to brown color. The stem changes from a bluish-green color to brown as the plant matures. Its habitat is in sunny locations on dry gravely soils, rock outcrops, roadsides, railroads, waste places, in grasslands, and on marsh edges.

Pollination occurs during the winter through the summer. The center spikelet is fertile whilst the lateral spikelets are male and infertile.

The small grains are edible, and this plant was part of the Eastern Agricultural Complex of cultivated plants used in the Pre-Columbian era by Native Americans. Before being displaced by agriculture based on maize, little barley may have been domesticated.

Hordeum comes from the Latin word horreō, horrēre "to bristle " and pusillum is the "nominative neuter singular of pusillus"- "very little, very small, tiny."